Improving airflow at charger/inverter compartment

[Rafael8008]

My 1998 Hunter 376 original inverter/charger gave up 2 summers ago. I have replaced it with a modern, more sophisticated unit from Renogy. The new one is a performance upgrade, but is also considerably larger. Now there is little clearance in the intended compartment under the settee. Full disclosure, I just can't imagine creating enough room with my existing house battery bank in the next compartment, to meet the manufacturer's requirements for free space around the inverter/charger. With the latest heat wave, I have noticed pretty regular overheating when on 30 Amp. shorepower. I return to the boat. There is an audible alarm on. The inverter/charger is disabled. The state of the house battery is somewhat discharged. The components are actually doing what it's supposed to do under these conditions.

Has anyone tried to force some airflow in the compartment under the settee bench in hopes of reducing the temperature? I was thinking of these little RV refrigerator fans. They are 12V. Diameter is 2 - 1/2 inches. In a perfect world, maybe they could run from the solar panel and never accidentally draw from the house battery bank?

Thoughts?

 

[colemj]

You likely won't be able to run them directly off the solar because most solar panel voltages are much higher than 12V. Otherwise, a fan can help. The example you posted is just 3 computer fans. You can buy computer fans inexpensively, and probably quieter ones than those.

If you are on shore power, with the inverter's transfer switch passing it through, and the batteries are charged and in float, the inverter/charger shouldn't really be doing much. I wouldn't expect it to overheat when mostly idle even in hot ambient conditions. Its internal fan should easily accommodate that.

Mark

 

[MFD]

I have considered doing something similar.
You can get pretty cheap programmable 12 volt temperature switches nowadays.
The switch itself will have minuscule power draw, and the fans will only be running when things are warm and the charger/inverter is doing work.

 

[JoeWhite]

Rafael, I use 12vdc computer fans such as the ones you display that I have mounted 4 of them on 1/4" starboard and placed it in the hatch and slightly open the hatch to provide air circulation inside when at the dock and using shore power. I used 12vdc adapter that is plugged in to the 110vac outlet to provide power. This way the house batteries are not drained in case the shore power fails. You can do the same.

 

[Maine Sail]

Renogy inverters run hot. Is it installed in the correct orientation? What gauge are the batt cables?

 

[marcham]

My settee benches have a whole bunch of holes near the kickplate for ventilation, is it the same on the 376? No issues with overheat with the Victron 3000W inverter below the settee, the fan rarely kicks in... Does it overheat when passing AC through as well or only when inverting?

 

[Rafael8008]

Thank you for all your thoughtful comments. I've ordered 4 individual 12V computer fans and a thermostatic switch. I've given up on the idea of solar driving these little fans.
In addition, I topped up all the lead battery cells, tested the specific gravity and charged the batteries, eliminating a nagging fear that battery charging was somehow compromised. There is also an ongoing solar panel replacement project. The solar panel will remain wired to the separate starter battery, just like the original factory install.

We used to live in a very urban location and spent many nights sleeping on the boat, kind of like a floating cottage, mostly plugged in at the dock. It was more common to fall asleep to the sound of the battery charger fan than not. There used to be tremendous shelter at the dock and in nearby bays, near NY. I was very tuned in to all boat sounds, alarms, pumps and insisted that everything performs exactly as intended. Our sailing agenda is now really limited to 1 or at most 2 nights at anchor.
Will try to take a few pics and post the results.